Boiler brace



Dec. 10, 1929. J. c;. BLUNT 1,738,982

BOILER BRACE Filed May 3, 1926 INVENTOR ATTO EY Patented Dec. 10, 1929 UNITED STATES BOILER BRACE Application filed May 3, 1926. Serial No. 106,214.

My invention relates to the bracingused in boilers or other pressure drums to secure the flat end heads to the barrel of the structure and has for its object an improvement in structure whereby a greater factor of safety is attainable at a substantial saving in cost.

In boiler construction the usual practice is to stay the end heads to the barrel by brace rods, secured by in connections to suitable attachment lugs fixed to the heads and the shell plates. At the end of the boiler where the back head is stayed to the outer wrapper sheet, the brace rods extend between longitudinal rows of stays, and lugs, for attaching the brace rods to the shell or wrapper sheet, are of a shape to fit in between the rows of stays. The connecting rivets of any such lugs are disposed so as to be between the transverse rows of the stays. It will, therefore, be seen that the form of a brace rod connection is determined by very definite conditions. It has been customary to form the forked ends of the rods in forging machines and weld such ends onto the rod bodies to produce the proper lengths. It has also been customary to form the attachment lugs used in various locations about the boiler from drop forgings. It is apparent, however, that a stay rod built up of sections welded together will not be as strong as rods made from the solid bar without welds, because of the element of uncertainty as to the strength of the weld as compared with the strength of the bar as rolled. It is likewise apparent that attachment lugs when made by the drop forging process may be less strong than intended due to the possible weakening caused by the intense heat to which the material must be subjected in order to form the proper shape.

In carrying out my invention, all elements of uncertainty in the strength of the brace rods and their connections are eliminated by forming the rods without welds and by fianging the attachment lugs from plate material at a lower heat than required for drop forging. I thereby utilize the full strength of the rods and connections and produce a stronger structure than where welded rods are used. or where connections are employed which have been burned in the process. of

forging. Economy is also efiected, since the labor for welding is saved and the costly drop forge dies and their maintenance are eliminated.

Figure 1 is a vertical longitudinal section '55 through the upper part of the rear end of a boiler, showing the back head stayed to the shell sheet by diagonal boiler braces embodying my invention; Fig. 2, a plan view, show ing the attachment of one of the braces to the back head; Fig. 3, a side elevation of one of the brace rods and its connections; Fig. 4, a plan View of one of the blanks from which the brackets at the front end of the rods are formed; Fig. 5, an inverted plan view of the bracket at the front end of the rod; Fig. 6, an end view, in elevation, of the bracket shown in Fig. 5; and, Fig. 7 a vertical transverse section through the boiler water space, showing the relation of the diagonal stays and the stay bolts.

The improvement claimed is hereinafter fully set forth.

In the practice of my invention, referring descriptively to the specific embodiment thereof which is herein exemplified, the wrapper sheet 2 of the boiler is riveted to the back head 3 and is also stayed to the fire-box crown sheet 4 by the stays 5. The brace lug 6 which is riveted to the back head is in the form of a T-section. One end of the brace rod 7 is forked so as to straddle the leg of the T-section, and the forked end 8 of the rod and the leg of the T have apertures, for the reception of the pin 9 by which these parts are secured. to each other. At their forward ends, the brace rods 7 terminate in a flattened apertured portion 10, which enters a j aw 11 of the bracket riveted to a shell plate or wrapper sheet 2 and is secured therein by the pin 12. The brace rods 7 are preferably made from stock the size of the body of the rod and have the jaws 8 formed thereon in a forging operation. The rods are left sufficiently long 95 to form an eye in their opposite ends for the pins 12, after determiningthe proper distance between centers of the pins 9 and 12. In this manner the brace rods 7 are formed from one piece of material without welds and conse- 1 between the stays, and the fore and aft centers of the rivets are proportioned to customary stay spacing so as to bring the rivet centers midway betweenthe transverse rows of stays, as is shown in Fig. 7. Furthermore, the thickness of the material between the two jaws is reduced at 11, for thepurpose of shortening, as much as possible, the distance between the center of the pin 12 and the inner face of the wrapper sheet 2, and thus preventing excessive strains being imposed on the rivets,13. In the process of forming the brackets 11 the material does not have to be subjected to the intense heat required to form a drop forging and consequently an unweakened construction'is produced.

I claim as myinvention and desire to secure by Letters Patent:

1., In combination with a diagonal stay rod for boilers formed from a single piece of stock, comprising an intermediate portion; a fork forged at one end of the rod integral with the said port-ion, provided with a pair of registering orifices disposed transversely of the fork for the reception of a pivot pin; and a flattened portion forged at the opposite endv of the rod integral with the said intermediate portion, provided wlth an orifice disposed transversely of the flattened portion, forthe reception of a pivot pin, parallel to the s'a'idregistering orifices, whereby the rod may move in the same lane about either endas a center of a brac ret pivotally connected to said flattened portion, of integral structure-comprising a base plate for connection with the b oiler; an d,a pair of lugs projecting from the plate, disposed one on each side of the flattened portion, having orifices registering with the orifice of the flattened portion, saidgplate being provided with a depressed portion between the lugs opposite the flattened portion, whereby the end of the rod may beidisposed nearer to the boiler wall to which it is secured; and a pivot pin in the said registering orifices.- I v 2; In a diagonal stay rod device for boilers,

the combination of an intermediate rod portion; a fork forged at one end of the intermediate portion; a flattened portion forged at the Opposite end of the said portion, said intermediate portion, forln and flattened portion forming a rod made from a single piece ofstock,&the members of the fork being proided with registering orifices, and the flattencd portion being provided with an orifice parallel with the registering orifices, whereby the rod may move in the same plane about either end as a center; a lug disposed in the slot of the fork, having an orifice registering with the orifices of the fork; a pivot pin disposed in the orifices of the fork and lug; a base plate extendinglaterally of the lug and formed integrally therewith, having orifices therein, disposed laterally of the lug for securing it to the boiler; a pair of lugs disposed one on each side of the flattened portion having orifices registering with the orifice of the flattened portion; a pivot pin disposed in the rifices of the pair of lugs and flattened portion; and a base plate between the pair of lugs and formed integrally therewith, the plate being longitudinally extended and oriiced in line with the rod for securing it to the boiler and provided with a depressed portion between the lugs opposite the flattened portion, whereby the end of the rod may be disposed nearer to the boiler wall to which it is secured.

3. In a diagonal stay rod device for boilers, the combination of an intermediate rod portion; means at one end of the rod portion for securing it to the boiler; a flattened portion forged at the opposite end of the rod portion, provided with an orifice, said intermediate portion and flattened portion being made from a single piece of stock; a sheet plate bracket having side portions turned up from an intermediate portion to form a base plate having orifices for securing it to the boiler and upstanding parallel lugs from a single piece of sheet stock, the lugs being disposed one on each side of the said flattened portion, provided with an orifice registering with the orifice of the flattened portion, said plate being provided with a depressed portion between the lugs opposite the flattened portion, whereby the end of the rod may be disposed nearer to the boiler wall to which it is secured; and a pivot pin in the said registering orifices.

4. In a diagonal stay rod device for boilers, the combination of an intermediate rod portion; means at one end of the rod portion for securing it to the boiler; a flattened portion forged at the opposite end of the rod portion, provided with an orifice, said intermediate portion and flattened portion being made from a single piece of stock; a base plate; a pair of lugs projecting from the plate disposed one on each side of the flattened portion', having orifices registering with the orifice of the flattened portion, said base plate having orifices for securing it to the boiler and being provided with a depressed portion between the lugs opposite the flattened portion, whereby the end of the rod may be disposed nearer to the boiler wall to which it is secured; and a pivot pin in the said registering orifices.

5. In a locomotive boiler, the combination of a back head; a shell sheet; an intermediate rod portion; a fork forged at one end of the intermediate portion; a flattened portion forged at the opposite end of the intermediate portion, said intermediate portion, fork, and flattened portion being made from a single piece of stock, the members of the fork being provided with registering orifices, and the flattened portion being provided with an orifiee parallel with the registering orifices, whereby the rod may move in the same plane about either end as a center; a lug disposed in the slot of the fork, having an orifice registering with the orifices of the fork; a pivot pin disposed in the orifices of the fork and lug; a base plate extending laterally of the lug and formed integrally therewith secured to the back head; a pair of lugs disposed one on each side of the flattened portion having orifices registering with the orifice of the flattened portion; a pivot pin disposed in the orifices of the lugs and flattened portion; and a base plate between the two lugs, the plate having longitudinal extensions secured to the shell sheet and being provided with a depressed portion between the lugs opposite the flattened portion, whereby the end of the rod is disposed nearer to the boiler wall to which it is secured.

6. In a diagonal stay rod device for boilers, the combination of a rod having a flattened portion on one end thereof provided with an orifice; a bracket pivotally secured to said end comprising a base plate, a pair of lugs projecting from the plate, disposed one on each side of the flattened portion, having orifices registering with the orifice of the flattened portion, said base plate having orifices for securing it to the boiler and being provided with a depressed portion between the lugs opposite the fiat portion, whereby the end of the rod may be disposed nearer to the boiler wall to which it is secured; and a pivot pin in the said registering orifices.

JAMES G. BLUN T. 

